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96 Chevy 3500 Wuz Misfiring Now Doesnt Start

Biguy Matt

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Biguy Matt Enthusiast

Biguy Matt

Posted
Posted

Hi everyone.

 

I drive a 96 chevy 3500 w/vortech 350 vin r w/4L80. Week before xmas, I washed under the hood. It sat in shop drying off for 30 minutes. When I went to pull it outside, it would not start and sounded like it was crossfiring or something. Kinda burped and farted.After removing cap and rotor for inspection (finding nothing) it eventually gives in to lots of cranking. It started and ran on what seemed to be 6 cyl then cleared up. Days following, it sometimes in mornings would actually misfire under part throttle and was fine under load. It would run fine after warming up. Didnt have time to deal with at time. Last weekend I started it and it ran for 5 min in -8 C. I drove for 15 min. During that 15 min, it did have the mis at part throttle and also backfired out exhaust twice. I parked it, and it sat for 2 h. Then when I went out to check it out, it would not start. It only farts and burps. It also kicksback while your cranking. It kickedback when it wouldnt start before. I checked for codes and found a few o2 codes. Never had engine lights ever. Dont have much time to spare now and its sitting in my driveway frozen. Any ideas? Not sure where to point my time. Any help would be great!

kuhl_530 Enthusiast

kuhl_530

Posted
Posted

A common problem with these engines are the coils. I would strongly suggest replacing the coil, cap, rotor, wires, spark plugs, and pvc valve. I'm 99% sure this will clear up your issue.

Biguy Matt Enthusiast

Biguy Matt

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Thanks, When problem first was apparent I tried my other coil thinking exactly that. I also checked cap & rotor and theyre not even that old and looked pretty good. Also went through wires and replaced 3 or 4 that were not so nice looking(worn through)still wouldnt start then. Have seen astro vans that would not start just from old corroded cap & rotor but this looks ok. Worked on customers truck once that had no spark.Same vintage of truck. He had also washed under his hood. Found wire from computer to ignition module had open. I ran a new wire and it worked. Im just trying to avoid needless replacement of parts as well as tow bill to my work. I still need to check out my plugs though. They arent that old either and im pretty up on the maintenance. I am looking/replacing all the stuff mentioned though.

Biguy Matt Enthusiast

Biguy Matt

Posted
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Posted

Problem solved!! Thank you KUHL 530 for your helpfull input. I changed the cap & rotor after looking at my wires and plugs. They were the worst looking parts, so I changed them first. Purs like a dragon again!

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